In a handwritten letter to Phillip and Barbara Butler sent in September, the Rev. William Aitcheson said he "sincerely regrets the suffering he caused" in January 1977, when he burned a cross in front of their College Park, Maryland, home. The couple, now in their 70s, were newlyweds at the time, and Phillip Butler had just returned home from serving in Vietnam.

Along with the letter, Aitcheson sent two checks worth $23,000 to the Butlers — money the family was supposed to receive from an initial lawsuit filed after the incident four decades ago. That figure had been determined by a court.

The Rev. William Aitcheson, a priest in the Roman Catholic Diocese of Arlington, Virginia.Catholic Diocese of Arlington / via AP

But Aitcheson, who was 23 at the time, was arrested and charged for multiple cross burnings and sentenced to 90 days in jail for criminal misdemeanor, The New York Times reported. He never paid the money.

Aitcheson's prison sentence was contingent on him revealing the names of other Klansmen, which he also did not do at the time, said NBC Washington. He was reportedly ordained as a priest in 1988.

At first, the Butlers refused to open Aitcheson's letter and the restitution, the Catholic Diocese of Arlington, of which Aitcheson belongs, said in a statement Friday. Now, the diocese added, the couple is willing to accept the checks and have also asked for an extra $9,600 to cover attorney's fees.

In his letter, which was obtained by local station WUSA, the repentant priest wrote: "You became my target at the time because I did not believe that people of different races should live together. I was blinded by hate and ignorance. … I believe now that all people can live together in peace regardless of race."

But the Butlers don't believe the money Aitcheson gave them is enough. They are still in pursuit of $68,000 more to account for the interest that would have accumulated over the past four decades, according to their attorney, Ted Williams.

He said the Butlers are also concerned that a former KKK leader could become a priest and alleged that the Roman Catholic Church knew about his past involvement in the Klan and should have reported it.

President Ronald Reagan and first lady Nancy, leave the home of Phillip and Barbara Butler, right, on May 3, 1982 after paying an impromptu visit to the Butler family in College Park, Maryland.Bettmann / Bettmann Archive

The archdiocese did not immediately return an email seeking comment Saturday.

Williams said that the Butlers are also planning a lawsuit against the church for attempting to obscure crucial information about his past actions. Williams also indicated that by the church giving Aitcheson a public platform in August to use for confessing his tainted past, it caused the family more harm.

"My actions were despicable," he wrote, adding, "When I think back on burning crosses, a threatening letter, and so on, I feel as though I am speaking of somebody else. It's hard to believe that was me."

The archdiocese in its statement Friday said that Aitcheson felt "a moral obligation to pay as much as he could" to the Butlers, and that the fees were paid out of his pocket and with the help of a "personal loan."

They didn't specify what his role within the church would become now.

"As this matter involving the Butler family and Fr. Aitcheson has only been resolved recently, plans for his future priestly ministry are still being discerned," the diocese said.